Sulfur-isotope study of the Mezica Mississippi Valley-type lead-zinc ore deposits, Slovenia

摘要

The Mississippi Valley-type lead-zinc deposits of Mezica are hosted by Middle/Upper Triassic Wetterstein platform carbonates in the Northern Karavanke, Slovenia. The main ore sulfides have negative δ~(34)S values within a range of more than 28 per thousand which support sulfide origin by bacterial sulfate reduction. Variations of δ~(34)S of galena and coarse-grained sphalerite at orefield scale are generally larger than the differences observed in single hand specimens. The results best support local δ~(34)S variations of the sulfide source, and that sulfur from disconformable orebodies originated from leaching of earlier sulfide species of conformable ore.